I think you-all are missing the point,though.
The point was MMT's claim that it is taxes that give dollars their value VS a claim that is the ability of the US to create wealth that gives the dollar value.
1] In economics only people with money are considered to be able to create economic demand.
2] He is right the bottle of water will always have some value. Even in 30s Germany the Mark had *some* value. My friend has a 1M Mark postage stamp. It took 1 M Marks to send a letter. But Marks had some small value.
3] You were ignoring the cost of moving the bottle of water from 'here' to the guy in the desert.
4] But getting back to the point. I really don't see how the bottle of water having a non zero value proves that it is the ability of the US to create wealth that gives the dollar value. And keeps that value from sinking pretty fast. Look at what happened in the Rev. War. The Contentental Congress printed dollars and spent them, but they fell in value fast. Maybe it was because the Congress could not impose taxes [it lacked the legal power to do so].
It makes sense that the need of adults to get some dollars to pay their taxes will give dollars some value and help dollars retain their value.
OTOH, it isn't clear to me how the wealth of the US would maintain the value of the dollar. Please explain this.